Agree! The bearded pic is much better.
There are some exceptions. My Dad was military, had a U.S. Navy crewcut with the exception of about six weeks. I’ve only seen the pictures, but the mustache lasted I think a week. The fuller version made him look clownish. Mom told him to trim the sides back. He did so and it was uneven. So he trimmed the longer side and it became shorter than the other. On try number four, Mom said nothing, just gave him the nαzι salute.  End of mustache!

One summer at our camp in New Hampshire, he just quit shaving altogether. His beard came in black, patches of gray, streaks of reddish brown, and one jowl white!  Furthermore, it was scraggly. All he needed was a pair of overalls, a plaid flannel shirt, straw hat, hay seed for his mouth, a still! 

He went back to work one day, shocked everyone he wanted to shock and at lunch, he went to the men’s locker room and shaved it all off.

You're right, that there are exceptions.  Some men can look just as masculine / virile without facial hair, but for the majority who don't, it's worth looking into.  As I mentioned, some Eastern cultures would consider you a sissy if you didn't have a beard.  Even when Western clergy would go to the East, they would grow out beards since they'd never be respected or taken seriously if they showed up there clean shaven.  Some of it is cultural, but there's something there that's just God's design for nature also.

I'm not a fan of the moustaches for sure, but more the look in that AI.

Yeah ... but very slightly.  Gives you a pretty good idea, and I wasn't about to spent 30 minutes looking for the top AI tool for this out there ... but it's enough to give you an idea.  I don't think that simply thinning out would suffice, though it migth help a bit, to remove some of that "baby fat" look, but it still wouldn't get him 10% of the way to where some facial hair would.

I once heard a phrase.

The difference between an attractive and unattractive person is millimetres. They are small changes but they also make him appear more masculine.

Really it depends on his bodfat %. You will be surprised just how much gets hidden when someone has a "strong" face but are even a little overweight. Of course if he doesn't have strong bone structure then a beard my be the way to go, if he can grow a good one.